Just in the year since the Newtown school shooting, at least 173 children under age 12 have died from gunshots in the U.S., according to original reporting and research by NBC News. Click on the photo for a timeline of the 173 deaths. From left to right, from top: Alton and Ashton Perry, Leonard J. Smith Jr., Aaron Vu; Middle: Sebastian Swartz, Tiana Ricks, Mia Lopez; Bottom: Antonio Santiago, Jaiden Dixon, Madison Dolford.

To mourn the 20 children and six educators killed a year ago at Sandy Hook elementary, residents of the Connecticut suburb of Newtown will take a quiet action on Saturday: placing candles in windows to remember the lives lost.

But who will put a candle in the window for the hundreds of American children each year killed in everyday violence, closer to home, usually by someone they knew?

The nightmare gripped parents across the nation after the pop-pop-pop of gunfire on a crisp December morning: a stranger in a school with guns. Although mass killings are watersheds in the American consciousness, it's easy to forget that more than 900 children in the U.S. die in homicides each year. And most of them perish at the hands of a relative, according to an NBC News analysis of 25 years of homicide reports submitted by police to the FBI. Only seven of every 100 child homicides are committed by strangers. See the patterns in child homicides.

"The high profile tragedies that glue us to the TV screen are a very small part of the overall problem, and they're not representative of it," said Garen Wintemute, a professor of emergency medicine and director of the Violence Prevention Research Program at the UC Davis School of Medicine. "If you take Sandy Hook and the Oak Creek Sikh temple shooting and Aurora and Virginia Tech and Columbine, 95 people were killed in those shootings. And each of those deaths is horrific. But we lose on average 88 people per day to firearm violence."

As part of its coverage of the Newtown anniversary, NBC News examined the broader patterns in homicides of children and spoke with researchers about the changes that could save young lives.

NBC News

See the toll guns take on youngest Americans in this interactive map and chart on children under 12 killed since Newtown. Click on the map to open.

The people of Newtown have decided against having a public memorial service on the Dec. 14 anniversary, but have asked residents to put a candle in the window to show their commitment to a year of public service, kindness and compassion. Families of victims have a new website, My Sandy Hook Family, for remembrances of those lost in the shooting at the neighborhood elementary school.

The patterns in homicides of childrenNBC News took a fresh look at killings of children, using detailed homicide reports submitted to the FBI by police departments across the nation from 1987 through 2011, the most recent available. The FBI records, for all ages, include 549,020 incidents with 574,774 victims. NBC focused on the homicides of 17,650 victims under age 12.

NBC News

Guns, homicide and America's children: Explore 24 years of FBI data on victims, killers, circumstances and weapons. Click on the image to open.

Four patterns emerge:

Few of the killers are strangers. Family members account for 51 percent of the killers. Other people known to the victim account for another 28 percent. Strangers are only 7 percent. And 13 percent of cases, the relationship status couldn't be determined.

Few killings of children happen during "street crime" or "gang violence." Arguments and home violence are far more deadly for children than getting caught up in a crime unfolding. Police reported only 13 percent of the homicides as happening during commission of another felony.

Guns are used in about one in four homicides of children under 12. Guns are not the No. 1 weapon in homicides of younger children. Why? Because so many of the children killed are very young. Babies rarely get shot, but they do get strangled or shaken, so the most often used "weapon" is hands or feet, at 34 percent. Next are guns, at 23 percent. The picture changes rapidly as one moves up the age range — older children can fight back or run away. By the time children are 3, the most common weapon in homicides is a gun. For all age groups, including adults, guns are used in 66 percent of homicides.

Most of the guns that kill children are handguns, which are far more commonly used than all other types of guns combined. The same pattern holds for adult victims.

Putting school shootings in perspectiveAmerica's schools and streets are safer than Americans know.

An average of 23 youths per year were the victims of homicides at elementary or secondary schools or on the way to a school event, from 1992 to 2011, according to the most complete federal study, by the U.S. Department of Education and the Bureau of Justice Statistics. And those deaths include all kinds of homicides — drug deals gone bad, fights over a girl — in a nation with 130,000 schools and more than 50 million students in grades K-12.

School violence is decreasing, just as the general crime rate has decreased steadily over the past 20 years. With the focus by the news media and public on crime, particularly gun crimes, the public is largely unaware that the gun homicide rate is down 49 percent from its peak in 1993. Most of the public believes incorrectly that gun crime is higher than two decades ago, according to a study from the Pew Research Center.

Every spike in homicides grabs public attention, but the general decline is little noticed, as few news stories reflect more than a single month or year. Consider Chicago, which is often cited by gun-rights activists as proof that gun-control laws do not work, because of its strict law and its spike in homicides in 2012. Did you know that this year Chicago is on track for its fewest homicides since 1965, continuing the general trend of fewer homicides in that city? The number of homicides in Chicago was consistently above 800 a year in the early 1990s, but has steadily dropped to below 500 recently, according to the Chicago Police Department.

Still, no one is arguing that the number of deaths is low enough. A child aged 5 through 14 in America is about 13 times more likely to be murdered with a gun than children in Japan, Italy or other industrial countries, according to the Harvard School of Public Health. (Watch the Harvard forum on gun violence.)

Ways to bring down gun violenceIs it possible to bring down the number of homicides of children without talking about guns?

From a gun-rights perspective, the National Rifle Association argues that guns make America safer, that the crime rate and the murder rate have been dropping — precisely because more people own guns and more states permit the carrying of concealed weapons.

"When the wolves can't distinguish the lions from the lambs, the whole flock is safer," wrote Wayne LaPierre, executive vice president and CEO of the NRA.

From a public health perspective, the American Psychological Association released a report Thursday on preventing gun violence, calling for actions based on scientific evidence, not politics.

"The prevention of gun violence might include efforts focused on guns — because guns are such a powerful tool for violence — but should also include other strategies such as conflict resolution programs and improved mental health services," the APA urged. "Measures to keep prohibited persons from accessing firearms, such as licensing handgun purchases, background checks for all gun sales and close oversight of gun retailers can reduce the diversion of guns to criminals."

Emergency physician Wintemute argues that the first step to protecting children is to shed the assumption that homicides are inevitable, that America has a uniquely high share of wolves. If one ranks the 36 developed nations on the rates of violent assault, he says, America is third from the bottom, relatively safe.

Not only homicides, but also suicides and accidental deaths, could be reduced by such steps. Suicides by gun are twice as common as gun homicides, according to data from the Centers for Disease Control. Most suicide attempts with a gun are successful, while most suicide attempts by other means are not, according to a Harvard School of Public Health study. In 2010, the latest year with final statistics, the CDC counted 19,392 suicides using guns, 11,078 homicides with guns, 606 accidental gun deaths and 252 gun deaths with undetermined cause. These figures don't count the 31,672 injuries with firearms.

MySandyHookFamily.org

The website of My Sandy Hook Family is a place for remembrances of the 20 first-graders and six educators killed at Sandy Hook Elementary School in Newtown, Conn., on Dec. 14, 2012. Click on the photo to go to the website mysandyhookfamily.org.

Each of these recommendations provokes a Second Amendment rebuttal. Wintemute found in a survey, for example, that a majority of gun sellers support tougher background checks and bans on purchases by people with histories of violence, mental illness or alcoholism-related crimes. That study, however, was opposed by the NRA, which sent out an email discouraging its members from participating. Wintemute received a copy of the email, because he's an NRA member.

The NRA says it doesn't oppose such technology — so long as governments don't require its use. "NRA does not oppose new technological developments in firearms," the NRA's lobbying group said in a recent news release. "However, we are opposed to government mandates that require the use of expensive, unreliable features, such as grips that would read your fingerprints before the gun will fire. And NRA recognizes that the 'smart guns' issue clearly has the potential to mesh with the anti-gunner's agenda, opening the door to a ban on all guns that do not possess the government-required technology."

Optimism or pessimism for action?Gun-control advocates have expressed their disillusionment with the inability of the Obama administration to get Congressional backing for changes such as background checks and limits on high-capacity magazines.

But Wintemute , who has researched gun violence for 30 years, said he is more optimistic.

"Washington is not the only place that change can happen," he said. "Change can happen in the home, in a doctor's office, in a state legislature. Lots of people are talking. There are an array of organizations committed to making change happen, and that's never happened before."

About the data:
NBC News looked at data for 25 years from the FBI's Supplemental Homicide Report, the most detailed database for studying homicides in America. Details include the type of weapon used in a crime, as well as the age, sex, and race of the victims and the offenders, and the relationship of the victims to the offenders. The data cover the years 1987 through 2011.
The FBI records, for all ages, include 549,020 incidents with 574,774 victims. The FBI records, for all ages, include 549,020 incidents with 574,774 victims. NBC focused on the homicides of 17,649 victims under age 12.
Not every homicide in the country is included. Although all 50 states and the District of Columbia are included in the data, in some years not every state participates in the voluntary reporting, and the participating police departments vary from year to year. NBC News also excluded reports from the terror attack of Sept. 11, 2011.

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